1. Field of the Invention
The invention relates to an anvil attachment about which a staple may be formed during a stapling operation, and more particularly to an anvil attachment to be affixed to the nose portion of a surgical stapling instrument or the like and which may be so configured as to provide anvil portions for two or more different sizes of staples.
2. Description of the Prior Art
While the anvil attachment of the present invention is capable of many applications, it will, for purposes of an exemplary showing, be described with respect to its use on a surgical stapling instrument for which it is particularly well adapted. Recently, surgeons have come more and more to the use of staples, rather than conventional thread sutures, for closing wounds or incisions in the skin and facia of a patient. This trend is due largely to the fact that the use of staples is a far easier procedure and, of even greater importance, is very much faster. This substantially reduces the time required for suturing and the length of time the patient must be maintained under anesthesia.
Prior art workers have devised a number of different types of surgical stapling instruments and staple carrying cartridges therefor. It is the usual practice to provide an anvil (about which the staples are formed) as an integral part of the staple cartridge. Examples of this are taught in the following U.S. Pat. Nos. 3,618,842; 3,638,847; 3,643,851; 3,650,453; 3,662,939; 3,717,294; 3,819,100 and 3,837,555. The provision of an anvil as an integral part of a cartridge structure makes the cartridge structure more complex in design and more expensive to manufacture. In many of the prior art cartridge-surgical stapling instrument systems the cartridge is supported only at one end by the surgical stapling instrument.
The anvil attachment of the present invention is intended to be affixed to the nose portion of a surgical stapling instrument and need not be disposed of with each staple cartridge used. The anvil attachment is intended for use with a cartridge of the type not having an anvil as an integral part of the cartridge. While not necessarily so limited, the anvil attachment is particularly adapted for use with the staple cartridge taught in U.S. Pat. No. 4,043,504.
The anvil attachment provides a simple and positive means for properly locating the staple cartridge on the surgical stapling instrument and for holding the bottom of the staple cartridge accurately and securely to the instrument. The anvil attachment may be configured to accommodate two or more different staple crown widths or sizes and enables simple self-centering of staples of both sizes. The anvil assembly may be readily and quickly attached to and removed from the surgical stapling instrument should replacement of the anvil attachment be necessary or should it be desired to change anvil attachments to accommodate other predetermined sets of staple crown widths.